Improvement in printing-telegraphs



T. A. EDISON.

Printing Telegraphs.

No. 139,128. Patented May 20,1873.

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UNITED STATES PATENT OFFICE.

THOMAS A. EDISON, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE GOLD AND STOCKTELEGRAPH COMPANY, OF NEW YORK, N. Y.

IMPROVEMENT lN Pi?lNT]hlG-TELEGRAPHS.

Specification forming part of Letters Patent No. 139,128, dated May 20,1873; application filed February 18, 1873.

To all whom it may concern:

Be it known that I, 'lnorms A. EnIsoN, of Newark, in the county of Essexand State of New Jersey, have invented an Improvement inPrinting-Clelegraph Instruments, of which the following is aspecification:

In this instrument there are three electromagnets, all in the main-linecircuit, and they are so adjusted that the pulsations act in one of themagnets to set the type-Wheel; but the other two magnets, dischargingmore slowly, act to hold down the printing-lever. \Vhen the circuit isbroken and a pause ensues the electro-magets all discharge, allowing aspring to the armature of one to draw back a hook and allow theprinting-lever to fly up by a spring. The next pulsation energizes allthe magnets,

drawin down the )rintin -lever and holdin b b b it: then the otherpulsations set the typewheel.

In the drawing, Figure 1 is a plan representing the improvement, andFig. 2 is a side view of the instrument.

The magnets to b c are in the main-line circuit, as seen in Fig. 1, sothat the pulsations energize all the magnets; the magnet 1), however, issmall, and so made as to rapidly discharge hence the pulsations act tomove the armature d. lever e, and pawl 1', and set the type-wheelf. lremark that the dog 3, shown by dotted lines in Fig. 2, blocks theratchetwheel to prevent it turning too far by the inertia, and the pawl4 prevents motion in the wrong direction. The magnet to acts upon thearmature h and hook it to hold down the print-- ing-lever k, and themagnet cis sntficiently powerful to draw down that lever is against theaction of the spring I.

Vhen the circuit is broken and a pause en sues the magnets a c dischargethemselves, and the spring at draws back the hook '5, allowing thespring l to throw up the printing-lever k and give the impression. Whena pulsation is sent again the three magnets a b c are energized,theprintin g-lever is drawn down by c and latched by the hook 72 untilanother pause on an open circuit occurs. The strip of paper passesbetween a sliding pawl, s, and a plate, 1', upon the printing-lever, andthis pawl 5 slides in a turning-stud, u, that is drawn back by a spring,0. Upon the shaft of the type-wheel f is a snail-wheel, t, shown bydotted lines in Fig. 2, the periphery of which is notched, of ditferent'distances from the center of the shaft, in accordance with. the.distance the paper is required to be fed for the letter impressed. Asthe printinglever lo rises, the end of the sliding pawl 8' comes intocontact with this snail-wheel, and the other end, clamping the paper,slides it upon the incline or surface r until the printing is effected.At the reverse movement the spring 0 draws the sliding pawl back to thenormal position.

I claim as my invention 1. Three magnets in the main-line circuit,operating as set forth, in combination with the type-wheel lever,printing-lever is, spring 1, and latch i, substantially as and for thepurposes set forth.

2. The sliding pawl s, in combination with the snail-wheel upon thetype-wheel shaft, and

the printinglever 7c, substantially as set forth, for feeding the paper.

3. A printing-lever and an electro-magnet arranged in connection withthe type-wheel and its magnet, substantially as set forth, so that theprinting-lever is drawn away from the type-wheel by the electro-magnet,and the printing is effected by breaking the circuit to theelectro-magnet.

Signed by me this 21st day of January, A. D. 1873.

THOMAS A. EDISON.

Witnesses:

GEO. '1. PINOKNEY, CHAS- E. SMITH.

